. The broad long-term objectives of this application are to define what the human lupus-type inclusions (LI) are; and their significance and role(s) in the immune-based diseases of SLE and AIDS. The specific aims of this proposal include determination of the reactivities of autoantibodies with untreated, and interferon-treated and LI-containing, cells; determination of the reactivities of oligonucleotide probes specific for RNA in SRNAS and in common viral RNAs; and to determine whether other cytokines can induce LI. Cell structures that react with the selected antisera will be stained with colloidal gold. RNA and proteins reacting with these antisera will be examined in protein and RNA polyacrylamide gels. The oligonucleotides will be synthesized following standard phosphoamidite chemistry, and the corresponding biotinylated cRNAs by T7 polymerase reactions. Hybridization to LI and detection by colloidal gold will follow published ultracytochemical protocols. The experimental design consists of culturing peripheral blood leukocytes and selected human lymphoblastoid cells with interferon and other cytokines. LI formation is determined with the electron microscopic examination of thin sections. The investigator believes that results from these studies will elucidate the relationship between the lupus-type inclusions and ribonucleoprotein autoantibodies and that these studies may identify LI components, and lead to their purification.